Carbocycle editing of ketones proceeds via a radical-mediated bidirectional C-C bond cleavage/coupling strategy.

1,n-Difunctionalized alkyl linchpins are pivotal building blocks in organic synthesis, functional materials, and pharmaceuticals. However, their preparation currently relies predominantly on de novo synthesis, which is hampered by low step-economy and poor functional group compatibility. Herein, we report an efficient method based on a radical-mediated bidirectional C-C bond cleavage, which enables simple cyclic ketones to function as potential diradical linchpins via the formation of gem-diperoxides. It employs a stepwise and controllable tandem process involving alkoxy radical-induced β-scission and acyloxy radical-mediated decarboxylation, to achieve ring-opening, carbon shrinkage, and bidirectional functionalization of carbocycles. This carbocycle editing protocol features sustainable metal catalysis, a broad substrate scope, and excellent functional group compatibility. Notably, the cascade reaction enables facile and selective editing of various complex natural products and drug molecules. This bidirectional C-C bond cleavage/coupling strategy allows for rapid and modular synthesis of structurally diverse alkyl 1,n-dithiocyanides, 1,n-diazides, 1,n-dihalides, and unsymmetric 1,n-thiocyanate-azides (n ≥ 4).